In this report we describe our progress toward understanding the biochemical mechanism of Bacillus megaterium QM B1551 spore germination. We have extended our previous studies on L-proline, L-leucine and glucose initiated germination. For the mechanism of amino acid initiated germination, the efficacy of nonmetabolizable analogues to initiate germination and the lack of a complete system of proline and leucine catabolic enzymes suggest that metabolism of the exogenous amino acid is not necessary. Similar results for glucose initiated germination were found and we have extended these observations by studying oxygen consumption, glucose transport and the involvement of a protonmotive force. Oxygen consumption occurred at about the time of absorbance loss, a late event in initiation of germination, and could be blocked without completely inhibiting initiation. Glucose uptake appeared to occur in two phases, the first (possibly energy independent) was at about the time of absorbance loss and the second (active transport) was 2-3 min. later. Based on inhibitor studies and direct measurement of pH drops during initiation of germination, we found not evidence for the necessity of a protonmotive force. Present efforts are directed toward identification of the glucose receptor site and a further analysis of amino acid initiated germination.